Loop taker lubrication for sewing machines

ABSTRACT

Apparatus for lubricating a loop taker raceway in a sewing machine wherein a current of air forces an oil mist through a hollow loop taker drive shaft and deflects the air laterally at the inlet port of the shaft, and wherein the oil is positively supplied with the quantity of supply of oil varying in accordance with the r.p.m. of the sewing machine.

United States Patent 119'] Von Hagen 1 Nov. 6, 1973 [54] LOOP TAKER LUBRICATION FOR SEWING 2,531,362 11/1950 Parry 112/256 MACHINES 2,762,325 9/1956 Hale et al. [12/256 [75] Inventor: Woll-Riidiger Von Hagen,

Grotzingen, Germany FOREIGN PATENTS OR APPLICATIONS 1,902,000 8/1970 Germany [12/256 [73] Assrgnee: Union Special Maschlnen labrik G.m.b.ll., Stuttgart, Germany [22] Filed: Nov. 12 1971 Primary Examiner-George H. Krizmanich Att0rneyCharles E. Brown et a]. [21] Appl. No.: 198,377

[30] Foreign Application Priority Data [57] ABSTRACT Nov. 25, 1970 Germany P 20 57 916.2

Apparatus for lubricating a loop taker raceway in a [52] US. Cl. 112/256 sewing a hine wherein a current of air forces an oil Int. mist through a hollow loop taker drive haft and del Field Of Search 1 134, flects the air laterally at the inlet port of the shaft, and 184/6-l5 wherein the oil is positively supplied with the quantity of supply of oil varying in accordance with the rpm. [56] Refer n Cited of the sewing machine.

UNITED STATES PATENTS 3,624,763 11/1971 Rohr 112/256 10 Claims, 2 Drawing Figures 1 LOOP TAKER LUBRICATION FOR SEWING MACHINES The invention relates to a loop taker lubrication system for sewing machines of the general type disclosed in the application of Gunter Rohr, Ser. No. 1,000, entitled Loop Taker Lubrication System, now U.S. Pat. No. 3,624,763, granted Nov. 30, 1971.

BACKGROUND OF THEINVENTION In the case of the loop taker lubrication system according to the aforementioned application, the delivery of lubricant to the loop taker is not always in accordance with the requirements of the loop taker because the lubricant is supplied by dripping off, in an-unequal manner, from a rib of. the machine base above a shiftable bolt which functions as a lubricant feed member. Also, the proportional increase of the lubricant supply with an increasing r.p.m. is not entirely satisfactory.

SUMMARY OF THE INVENTION Although the lubrication system of application Ser. No. l,000, does greatly improve the lubrication of the loop taker, the aforementioned deficiencies are objectionable and it is the object of this invention to improve the loop taker lubrication system disclosed in that aforementioned copending application in a manner to eliminate these deficiencies.

' This object is achieved in that the shiftable bolt,

which has received the dripping lubricant and which is provided with a conical end engaging with the intake stackof the fan for effecting lubricant flow, has been provided with a channel or bore for the positive delivery of lubricant to the intake stack of the fan, whereby the lubricant is supplied under pressure and wherein which pressure changes in dependence on the r.p.m. of the sewing machine. Preferably, the lubricant is fed into the channel by way of an annular groove in the exterior of the bolt and through-radial bores with the lubricant being supplied through the main shaft of the sewing machine from the normal lubricant supply thereof.

Asa result of this modification of the loop taker lubrication system, the loop taker will receive a quantity of lubricant which increases proportionately with the r.p.m. of the sewing machine and the quantity of the lubricant delivered to the loop taker can be regulated by the axial shifting of the bolt. The lubricant is supplied under pressure to the channel in the bolt and reaches the intake stack of the fan through the channel. Depending on the adjustment of the conical end of the bolt to the intake stack, this flow of lubricant is conveyed to the loop taker shaft or is centrifuged off by way of the fan. As a result of the change in pressure of the lubricant in dependence of the r.p.m. of the sewing machine, the quantity of lubricant flowing to the loop taker in each adjusted position of the bolt changes in proportion to the r.p.m. of the machine.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary vertical sectional view through a base of a sewing machine taken along the drive shaft for the loop taker.

.FIG. 2 is a bottom plan view of the mechanism of FIG. 1, partially in section, with the usual bottom cover removed.

A base of a sewing machine 1 is provided with antifriction bearings for journalling a loop taker drive shaft 2 for rotation and for driving a conventional loop taker 3, in the conventional manner. A main shaft 6 of the sewing machine drives the loop taker drive shaft 2 in a conventional manner through a drive gear 7 mounted on the main shaft 6 and a driven gear 5 secured to the loop taker drive shaft 2.

At this time it is pointed out that the loop taker drive shaft 2 is provided with a concentric bore 8 through which lubricant flows to the loop taker 3. The bore 8 includes an inlet port 10.

The base of the sewing machine 1 is closed at its bottom side by a removable cover plate 9 thereby'providing an oil reservoir chamber 11. Previously, an oil mist created in the chamber 1 1 was forced into the inlet port 9 and served as the sole supply of lubricant for the loop taker 3. As was previously disclosed in the aforementioned application Ser. .No. 1,000, the sewing machine 1 includes a fan 12 which is secured to the loop taker drive shaft 2 and which is provided with radial blades 13. The fan 12 also has an axially extending intake opening or stack 14, the size of the inlet opening 14 being adjustable by the provision of a conical end 15 of an axially displaceable bolt 16 being located in the opening 14 in concentric relation thereto. The bolt 16 is journaled for axial displacement in the base of the sewing machine 1 and includes an annular groove 17 into which engages an eccentrically arranged pin or stud l8 projecting from the end face of an adjusting shaft 19.

In accordance with the present invention, the bolt 16 is provided with an axial bore 21 opening at one end into a nozzle-likebore 22 in the conical end 15 of the bolt. The other end of the bore 21 is closed by a plug 23. The axial bore 21 is in communication with the annular groove 17 by means of radial bores 24.

The base of the sewing machine 1 is provided with a lubricant chamber 25 which is formed by a continuation of the bore receiving the adjusting shaft 19. The lubricant chamber 25 extends to a bushing type bearing 26 for the main shaft 6. The main shaft 6 of the sewing machine is provided in a conventional manner with an axial bore 27 which is in constant communication .with an annular groove 29 formed in the bearing 26 through radial bores 28 formed in the shaft 6. A further radial bore 30 is formed in the bearing 26 and leads from the annular groove 29 into the lubricant chamber 25.

It will be readily apparent that the radial bores 28 formed in the main shaft 6 of the sewing machine function as pump elements and centrifuge lubricants from the axial bore 27 into the annular groove 29. The higher the r.p.m. of the main shaft 6, the higher will be the speed of the lubricant and thus the pressure of the lubricantcentrifuged into the annular groove 29 because of the centrifugal force. From the annular groove 29, the lubricant passes into the chamber 25 and moves from there through the bore or channel 21 and nozzle 22 into the intake stack or opening 14 of the fan 12. The closer the conical end of the bolt 16 is positioned with reference to the intake opening 14, the less air will be sucked in between the conical end 15 and the portion of the fan 12 defining the intake stack 14. As a result of that, the lubricant emerging from the nozzle 22 will be largely hurled away by the blades 13 of the fan 12 and only a small quantity of lubricant reaches the bore 8 in the loop taker drive shaft 2. However, this small quantity of lubricant, as determined by the adjustment of the bolt 16, will vary proportionately with the r.p.m. of the sewing machine.

If the conical end 15 is moved further away from the intake stack 14 of the fan, then more air will be sucked in and will be forced to the outside by the blades 13 instead of the lubricant. As a result of such adjustment, more lubricant can reach the bore 8 of the loop taker drive shaft 2 for delivery to the loop taker 3.

It is to be understood that it is also possible within the scope of the invention to feed the lubricant to the bore or channel 21 in the bolt 16 by means of a different type of pump. However, such pump should have an output dependent upon the rpm. of the sewing machine.

Although only a preferred embodiment of the invention has been specifically illustrated and described herein, it is to be understood that minor variations may be made in the disclosed lubrication system without departing from the spirit and scope of the invention, as defined by the appended claims.

I claim:

1 Lubrication apparatus for a sewing machine comprising a loop taker driven by a loop taker drive shaft and said loop taker drive shaft having a bore therethrough for a lubricant, a fan carried by said loop taker drive shaft, said fan having an axial inlet and being of the radial discharge type, said loop taker drive shaft having an end terminating within said fan in alignment with said inlet and in the path of axial flow through said fan with said bore being positioned for forming a continuation of said inlet, an air flow controlling member positioned within said inlet, lubrication supply means for supplying lubricant into said inlet both to and around said loop taker driving shaft bore, said lubricant supply means including a lubricant supply passage opening axially through said air flow controlling member into said inlet with lubricant supplied thereby in part being received within said loop taker drive shaft bore and in part expelled radially by said fan, said air flow controlling member forming means for varying the flow of air into said inlet and the relative proportion of lubricant flowing into said loop taker drive shaft and lubricant being expelled by said fan.

2. The lubrication apparatus of claim 1 together with adjusting means for axially adjusting the position of said air flow controlling member in said fan inlet to vary the flow of air into said inlet and thereby vary the relative proportion of lubricant flowing into said loop taker drive shaft and lubricant being expelled by said fan.

3. The lubrication apparatus of claim 2 wherein said adjusting means includes an annular groove in said air flow controlling member and an eccentric pin seated in said annular groove, and said lubricant supply means includes means placing said annular groove in communication with said lubricant supply passage with said annular groove forming an inlet for said lubricant supply passage.

4. The lubrication apparatus of claim 3 wherein said eccentric pin is carried by a shaft seated in a bore in said sewing machine, and said lubricant supply means also includes said last mentioned bore extending transversely of and beyond said air flow controlling member and forming a lubricant supply passage in communication with said groove.

5. The lubrication apparatus of claim 4 wherein said sewing machine includes a main shaft, drive means connecting said loop taker drive shaft to said main shaft, and said lubricant supply means further includes said main shaft having supply means for supplying lubricant under pressure to said lubricant supply passage.

6. The lubrication apparatus of claim 5 wherein said main shaft pump has pump means of variable output in accordance with the speed of rotation thereof.

7. The lubrication apparatus of claim 2 wherein said lubricant supply means includes means for supplying lubricant to said supply passage under pressure.

8. The lubrication apparatus of claim 2 wherein said lubricant supply means includes means for supplying lubricant to said supply passage under pressure and in accordance with the operating speed of said sewing machine.

9. The lubrication apparatus of claim 1 wherein said lubricant supply means includes means for supplying lubricant to said supply passage under pressure.

10. The lubrication apparatus of claim 9 wherein said lubricant supply means includes means for supplying lubricant to said supply passage under pressure and in accordance with the operating speed of said sewing machine. 

1. Lubrication apparatus for a sewing machine comprising a loop taker driven by a loop taker drive shaft and said loop taker drive shaft having a bore therethrough for a lubricant, a fan carried by said loop taker drive shaft, said fan having an axial inlet and being of the radial discharge type, said loop taker drive shaft having an end terminating within said fan in alignment with said inlet and in the path of axial flow through said fan with said bore being positioned for forming a continuation of said inlet, an air flow controlling member positioned within said inlet, lubrication supply means for supplying lubricant into said inlet both to and around said loop taker driving shaft bore, said lubricant supply means including a lubricant supply passage opening axially through said air flow controlling member into said inlet with lubricant supplied thereby in part being received within said loop taker drive shaft bore and in part expelled radially by said fan, said air flow controlling member forming means for varying the flow of air into said inlet and the relative proportion of lubricant flowing into said loop taker drive shaft and lubricant being expelled by said fan.
 2. The lubrication apparatus of claim 1 together with adjusting means for axially adjusting the position of said air flow controlling member in said fan inlet to vary the flow of air into said inlet and thereby vary the relative proportion of lubricant flowing into said loop taker drive shaft and lubricant being expelled by said fan.
 3. The lubrication apparatus of claim 2 wherein said adjusting means includes an annular groove in said air flow controlling member and an eccentric pin seated in said annular groove, and said lubricant supply means includes means placing said annular groove in communication with said lubricant supply passage with said annular groove forming an inlet for said lubricant supply passage.
 4. The lubrication apparatus of claim 3 wherein said eccentric pin is carried by a shaft seated in a bore in said sewing machine, and said lubricant supply means also includes said last mentioned bore extending transversely of and beyond said air flow controlling member and forming a lubricant supply passage in communication with said groove.
 5. The lubrication apparatus of claim 4 wherein said sewing machine includes a main shaft, drive means connecting said loop taker drive shaft to said main shaft, and said lubricant supply means further includes said main shaft having supply means for supplying lubricant under pressure to said lubricant supply passage.
 6. The lubrication apparatus of claim 5 wherein said main shaft pump has pump means of variable output in accordance with the speed of rotation thereof.
 7. The lubrication apparatus of claim 2 wherein said lubricant supply means includes means for supplying lubricant to said supply passage under pressure.
 8. The lubrication apparatus of claim 2 wherein said lubricant supply means includes means for supplying lubricant to said supply passage under pressure and in accordance with the operating speed of said sewing machine.
 9. The lubrication apparatus of claim 1 whErein said lubricant supply means includes means for supplying lubricant to said supply passage under pressure.
 10. The lubrication apparatus of claim 9 wherein said lubricant supply means includes means for supplying lubricant to said supply passage under pressure and in accordance with the operating speed of said sewing machine. 